Reactive oxygen species scavenging activity during periodontal mucoperiosteal healing: an experimental study in dogs

Excessive release of reactive oxygen species (ROS) in wounded tissue due to inflammation and ischaemia is a deleterious and destructive phenomenon for the healing process. Hence, scavenging of ROS is one of the essential steps in normal wound repair. In this study, we presented a profile of free radical scavenging enzyme (FRSE) activity of periodontal mucoperiosteal wounds in order to investigate ROS activity during periodontal wound healing. Mucoperiosteal periodontal flaps were elevated in the mandibular buccal region of seven dogs between the first premolar and first molar teeth, creating acute incisional wounds in the inner side of the flaps and they were replaced 30 min after elevation. Gingival samples taken from certain biopsy regions at baseline (before flap elevation), day 3, 12, 21 and 30 were processed for detection of active amounts of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX). All enzyme activities had increased by more than 100% of their baseline levels by day 3. SOD activity decreased gradually from days 3 to 30 and reached a level lower than the baseline value. The increase in CAT activity continued until day 21, and decreased to a level higher than the baseline value by day 30. GPX also decreased from day 3, and reached a level less than its baseline value by day 30. Our results suggest that FRSEs may contribute to the detoxification of ROS during periodontal mucoperiosteal healing. This relationship may be utilized to facilitate soft tissue and/or flap management in periodontal or intra-oral treatments.